Originally Posted by
TheOtherDave™
Yep. You've nailed it.. you need the matching ECU for your motor.
The B18B1's ECU fuel map is suited for a smaller displacement motor (obivously) and it stands to reason that the injector cycle is a little too short for the B20B.
Moved to Engine Swaps..
that is BS the b18b actually has a higher compression ratio and requires a larger amount of fuel. if anything the b20 needs less fuel. i have seen many dyno maps and the b20 using the b18b ecu usually needs fuel taken out. there are other issues here